Why are foundations essential for high-rise buildings? They are especially crucial in areas with weak or unstable soil layers. Without a strong foundation, buildings can settle unevenly or even tilt over time. Key Takeaways from the Image: 1. Shallow Foundations on Weak Soil Lead to Tilting and Settlement • The left side of the image shows buildings resting on shallow foundations in clay soil, which is weak and compressible. • Over time, these buildings experience uneven settlement, leading to tilting and potential structural failure. 2. Deep Foundations Reach Stable Soil or Bedrock • The right side of the image shows a building supported by deep foundation piles that extend through weak soil layers (clay, silt, sand) and anchor into the rocky soil (bedrock). • This provides stability and load-bearing capacity, preventing settlement and tilting. Why Use Deep Foundations? • Increases Load-Bearing Capacity: Transfers the building’s load to a stronger, more stable layer. • Prevents Differential Settlement: Avoids uneven sinking that can cause structural damage. • Improves Stability in Weak Soils: Essential for areas with soft clay, loose sand, or high water tables. • Ensures Long-Term Durability: Reduces risks associated with soil movement and foundation failures. Conclusion: Deep foundations (e.g., piles, caissons) are necessary when surface soils cannot support a structure’s weight. They provide stability, safety, and durability, especially for high-rise buildings, bridges, and heavy structures.